Drive-chain



m. 6|4,922. Patented Nov. 29, I898.

B. ABEL'L.

DRIVE CHAIN.

(Application filed Apr. 3,

(No Model.)

\x/n-wessss JSMAQK IM/QNTU m MW the apertures in the blocks, and reducedend UNITED STATES PATENT ()FFICE.

ROLLIN ABELL, OF BOSTON, MASSACHUSETTS.

DRIVE-CHAIN.

SPECIFICATION forming part of Letters Patent No. 614,922, dated November29, 1898.

Application filed April 1 3, l 8 9 8.

To all whom it may concern.-

Be it known that I, RoLLIN ABELL, of Boston, in the county of Suffolkand State of Mas-- sachusetts, have invented certain new and usefulImprovements in Drive Chains, of which the following is a specification.

This invention relates to drive-chains for bicycles and other machinery;and it consists in those features of novelty in construction andarrangement which I shall now proceed to describe and claim.

Of the drawings accompanying and forming a part of this specification,Figure 1 represents a view in side elevation and section, showing partof a sprocket-wheel and a chain thereon constructed in accordance withmy invention. Fig. 2 represents a section on the line 2 2 of Fig. 1,looking in the direction of the arrow as. Fig. 3 represents a section onthe line 3 3 of Fig. 1, looking in the direction of the arrow y. Figs. 4to 7, inclusive, represent detail views in perspective, elevation,section, and plan, showing myinvention embodied in a separable chain.Fig. Sis a view showing the operation of the chain when under tension ona sprocket-wheel, such as the rear sprocket-wheel of a bicycle.

The same reference characters indicate the same parts in all thefigures.

In carrying out my invention as illustrated in Figs. 1 to 7, inclusive,I depart from the common construction of bicycle chains in which thebearing-pins extending through the apertures in the blocks are employedas rivetpins to hold the side links in place and provide instead thirdpins connecting the side links at points between adjacent blocks andacting as rivet-pins. These third pins rest on the tops of thesprocket-wheel teeth, preventing the blocks from bottoming between theteeth, as will be hereinafter more fully set forth. The constructionalso permits of the use of hardened bearing-pins.

In the drawings, a may represent the forward sprocket-wheel of abicycle, having teeth or sprockets a a of the normal size.

B represents a portion of a chain, in which Z] I) are blocks of ordinaryformation, having apertures b b at either end for the reception ofbearing-pins c c. The latter are formed with enlarged middle portions 2,occupying Serial No. 677,402. (No model.)

portions 3 3, occupying apertures d d in the side links or plates 61 d.These bearing-pins instead of being upset or headed outside of theblocks, as usual, merely have their reduced portions passed through theside-links, making a tight fit, and the ends of the pins are preferablyflush with the outside of the links, Fig. 3.

e e are rivet-pins connecting opposite side links between the blocks,the said pins being shouldered and upset or headed outside of the links(see Fig. 2) after being assembled. The bearing-pins c c are given theirfinal form before being put in the chain and may therefore be hardenedto reduce wear.

To accommodate the rivet-pins e e, the side links cl d are formed withears 01 d projecting above the blocks, and said rivet-pins arepreferably located at such a distance above the pitch-line of the chainthat they will rest or sit on the convex tops or crests of the teeth andequidistant from both the next adjacent teeth in both front and rearsprocket-wheels, and also prevent the blocks 1) b from bottoming betweenthe sprocket-wheel teeth. This is an important consideration in reducingfriction, for when a driving tension is put on a chain of the ordinaryconstruction a block in passing onto atooth tends to grind against thebase of the tooth, thus producing friction, and when mud or dirt isthrown into the sprocket or chain the friction is greatly increased. Inmy improved chain the grinding of the blocks against the teeth islargely done away with and there is verylittle increase of friction dueto mud or dirt, for the dirt is givena chance to work out between theblocks and the bases of the teeth.

The present invention also provides a chain having a straight-line pull.This may be understood by referring to Fig. 8. 4 and 5 are twosuccessive or contiguous points at which the power of the chain isapplied to the rear sprocket-wheel f. Since the chain in action ispulling on itself, each link drawing on the following one, it has atendency to straighten. between these two points. This tendency isresisted in a chain of the ordinary construction by reason of the blocksbottoming against the sprocket-wheel between the teeth; but in thepresent construction each link is pivoted or adapted to rock on top of atooth, and the chain is thereby permitted to assume a number ofstraightdine segments on the sprocketwheel, each segment embracing threecontiguous bearing-pins o, as illustrated in Fig.8.

Figs. 4 to 7, inclusive, illustrate a modification of my invention. Thisform difiers from the one above described in the employment of removablelocking-pins e, connecting the side links 01 d. The latter are formedwith buttonhole-slots d (1 through the lower or enlarged portions ofwhich the pins may be introduced or removed at any time. The upper ornarrower portions of the slots are preferably parallel-sided and thepins are permanently grooved at both ends to form neck portions, whichoccupy the upper or narrower portions of the slots 01 and are heldtherein by friction. \Vhen the chain is in action, the only tendency ofthe sprockets is to force the pins farther up into their slots, and bymaking said pins fit tightly they will have no tendency to fall out ofplace. By constructing the chain in this manner all of the parts may bereadily assembled and re moved without the use of special tools andwithout mutilation. The chain, as will be seen, may be easily shortenedor lengthened by the removal or addition of links and may be quicklyrepaired in case of breakage on the road.

I claim- 1. The combination with a sprocket-wheel having its teeth ofthe usual form, of a chain certain parts or members whereof arecentrally provided with rivet-pins which when the chain is in operativeaction rest on the tops or crests of said teeth, substantially as shownand described.

2. In combination with a sprocket-wheel of usual form, of a chain partswhereof are centrally provided with rivet-pins which when the chain isin action rest on the crests or tops of the teeth of said wheel, andblocks of the chain hanging between said teeth, all substantially asshown and described.

A drive chain comprising apertured blocks, apertured side links,bearing-pins occupying the apertures in the blocks and side links, andrivet-pins central of and connecting the side links between the blocks,the blocks lodging or hanging in the spaces between the teeth of awheel, substantially as shown and described.

4:. A drive chain comprising apertured blocks, apertured side links,bearing-pins occupying the apertures in the blocks and side links, andrivet-pins central of and connecting the side links between the blocksand adapted to rest on the tops of sprocket-teeth, and equidistant fromthe next adjacent teeth.

5. In combination with a sprocket-wheel, a drive-chain comprisingapertured blocks, apertured side links, bearing-pins occupying theapertures in the blocks and side links, and rivet-pins connecting theside links between the blocks, and resting on the tops of thesprocket-teeth, and equidistant from the next adjacent teeth.

6. The combination with an ordinary sprocket-wheel and with the teeth orsprockets thereof, of a chain composed of blocks or parts which arelodged between the teeth and have an endwise driving-bearing on thesides of the teeth, and of other parts which have a transversesupporting-bearin g directly 011 the tops or crests of the teeth.

7. A separable drive-chain comprising apertured blocks, apertured andslotted side links, bearing-pins occupying the apertures in the blocksand side links, and annularlygrooved locking-pins occupying the slots inthe side links and connecting said side links at points between theblocks.

8. A separable drive-chain comprising apertured blocks, apertured andslotted side links, headless bearing-pins occupying the apertures in theblocks and side links, and removable grooved locking-pins occupying theslots in the side links and connecting said side links at points betweenthe blocks.

In testimony whereof I have aflixed my signature in presence of twowitnesses.

ROLLIN ABELL.

W'itnesses:

P. W. PEZZETTI, 0. F. BROWN.

